I just download this using WU, and after installation MSE reported v4.5.216.0, so it should be available on WU now. I'll update the first post when MS releases this version on the Download Centre
No, it was in windows vista/7 but in windows 8 is no longer function like that "Windows Defender was released with Windows Vista and Windows 7, serving as their built-in antispyware componente. Windows Defender is superseded by Microsoft Security Essentials, an antimalware product from Microsoft which provides protection against a wider range of malware. Upon installation, Microsoft Security Essentials disables Windows Defender and takes over its duty. In Windows 8, Microsoft upgraded Windows Defender into an antivirus program comparable to Microsoft Security Essentials.This new Windows Defender greatly resembles Microsoft Security Essentials and uses the same virus definition updates. As a result, Microsoft Security Essentials is not compatible with Windows 8".
Actually even in Win 8/8.x Windows Defender is default AV, it has nearly the same functionality as MSE. Unfortunately both act very aggressive in case MTK or other tools are detected .
I've heard of it but never had problems with both installed. Right now what kind of aggressiveness you talk about?
New MSE Pre-Release build is now available, version 4.6.205.0! This is available on first post of this thread.
This only happens if you're running Windows 8/8.1, cause Windows Defender is included with these OS versions! First Post has been updated because MSE v4.6.305.0 RTM has been released.